1. Field of the Invention
The present invention relates to an improved fin attachment and, more particularly, relates to an attachment for detachably connecting a pair of members in predetermined angular relation. Most particularly, the subject invention relates to such an attachment for individually mounting control fins on a missile so that each fin may be repeatedly, quickly, and conveniently attached and detached.
2. Description of the Prior Art
Missiles are commonly provided with fins for aerodynamic guidance. The fins may be fixed when a missile is in flight or may pivot to control the course of the missile. To reduce the bulk of a missile for shipping and storage the fins are not attached until the missile is ready for use. If the missile is not fired, as is often the case in a missile for launching from an aircraft, it is necessary to remove the missile from the aircraft and then to detach each fin before restorage of the missile. The attachment and detachment of each fin often occurs under adverse circumstances, as in the dark on the tossing deck of an aircraft carrier. Nevertheless, the fin must be quickly attachable and detachable and, when attached, be rigidly connected to the missile in predetermined angular relation even though the fin has been previously dismounted and remounted many times. The need for rigidity and precision in mounting is particularly important for control fins in which "flutter" and imprecise angular relation may render a missile guidance system ineffective. It is, of course, undesirable to provide unneccessary openings into the interior of a missile body, so that suitable missile fin attachments must be operable from the exterior of the missile and with limited access to the member on which the fin is mounted.
A number of prior art attachments have been utilized for detachably mounting a missile fin. However, such prior art attachments have one or more difficiencies such as allowing flutter of the fin, having parts which may be lost when a fin is removed, requiring undesirable use of tools, having members which are of unusual shapes or require close tolerances and are expensive to manufacture, or by having members which are easily damaged by carelessness when the fin is mounted and/or eventually damaged even when care is used.
It is known to connect a pair of members in a fixed angular relation by an inner ring and an outer ring having individual and conforming frusto-conical surfaces, the rings being urged together axially so that the outer ring expands against one member while the inner ring contracts against the other member. The rings thus clamp the members in fixed angular relation and yet allow the members to be released when the rings are relaxed. However, insofar as is known to the inventor, such rings have not been used to mount missile fins to a missile body, previous arrangements for using such rings being unsuited for missile fin mountings due to including a multitude of parts which are loose when the members are disconnected and to requiring substantial access to both members while they are being attached or detached.